Pipe boring machine



Nov. 28, 1950 B, GUYER 2,531,909

PIPE BORING MACHINE Filed May 2l, 1946 7.5: D i se "JIL Patented Nov.28, 1950 UNITED lSTATES PATENT OFFICE PIPE BORING MACHINE Biada Guyer,Denver, Colo.

Application May 21, 194e, serial No. 671,363

3 claims. (Ci. 255-20) In laying ground pipe, more especially serviceconnections to water and gas mains, it is customary to excavate at eachextremity of the run and to bore between the excavations by forcing thepipe through the ground while simultaneously rotating it with a wrench.If necessary, water may be forced through the pipe to assist the boring.It is, however, exceedingly difficult to apply the necessary pressure onthe pipe while rotating it with the usual pipe wrench.

This invention relates t'o what might be termed a pipe boring jack; thatis, a device for gripping the pipe and forcing it into the earth 'ohjarotating spiral. x

The principal obj'e'ct'jof the invention is to provide a sturdy, easilyportable pipe boring jack which can be readily handled in a smallexcavation; which 'can be used to force a pipe forwardly in a series ofsteps; and which will simultaneously rotate the pipe during each forcingstep.

Other objects and advantages reside in the detail construction of theinvention, which is designed for simplicity, economy, and eiiciency.These will become more apparent from the following description.

In the following detailed description of the invention, reference is hadto the accompanying drawing which forms a part hereof. Like numeralsrefer to like parts in all views of the drawing and throughout thedescription.

In the drawing:

Fig. 1 is a plan view of the improved pipe forcing device;

Fig. 2 is a side view thereof;

Fig. 3 is a forward end View; and

Fig. 4 is a cross-section, taken on the line 4 4, Fig. 2.

The improved pipe boring jack comprises a substantially rectangular baseframe It) having an upstanding front end member II and a similarlyupstanding rear end member I2.

A pipe-receiving tube I3 is rotatably mounted in bearing members I4 on asliding carriage I5. The carriage I5 is slidably supported on twoparallel slide rods I8 extending horizontally between the end members Iland I2. A flange plate I'I is fixed to or formed on the tube I3 inspaced relation to the forward extremity thereof.

A ring gear I8 rotatably surrounds the latter extremity and restsagainst the flange plate I'I. A pair of stop pins I9 extend from theflange plate I1 through circumferentially slotted openings in the ringgear to allow a limited rotation of the latter. A pair of tangentiallyinvrack 25.

clind ratchet dogs 2| are hinged at their outer extremities on hingescrews 22 in the face of the ring gear and extend through guide openings32 in the forward extremity of the tube I3 into the interior thereof.

An operating handle 23 is mounted on a handle shaft 24 extendingtra'sversally of the frame Il).l The handle 23 carries an arcuate,toothed rack 25 positioned to mesh with the teeth of the ring gear I8.Avst'ud 26 projects outwardly from the carriage I5 into van elongatedslot I2I in the handle 23 so that, as the handle is swung forwardly, thestud will move the carriage I5 forwardly, always maintaining the teethof the ring gear I8 in mesh 'with the teeth of the The 'pipe uponwl'iich` the device is to operate is indicated in broken line at 28.This pipe is passed over a grooved supporting roller 29 in the endmember I2, thence through the tube '13. A weighted, eccentric cam 30rests upon the pipe 28 over the roller 29 to prevent reverse movement ofthe pipe.

In operation, the extremity of the pipe 28 is placed againstv the wallof the excavation and the lever 23 is forced forwardly. This causes thestud 26 to move the carriage I5 forwardly, and also causes the rack 25to rotate the gear I8. The initial rotation of the gear I8 urges thedogs 2I inwardly through the guide openings 32 against the oppositesides of the pipe. When the pipe has been rrnly gripped by the dogs, thering gear I8, the tube I3, and the pipe 28 will move forwardly as a unitwith a spiral motion.

When the extremity of movement has been reached, the lever 23 is pulledrearwardly, the dog 30 preventing the pipe 28 from moving rearwardly.This reverses the ring gear I S on the extremity of the tube I3 to causeit to withdraw the dogs 2| from the pipe and allow them to moverearwardly to a newl gripping position when the process is repeated.Thus, the pipe is forced with a spiral movement in a series of steps.Water may be supplied to the pipe 28 through a conventional swivelconnection to assist the boring, if desired.

While a specic form of the improvement has been described andillustrated herein, it is desired to be understood that the same may bevaried, within the scope of the appended claims, without departing fromthe spirit of the invention.

Having thus described the invention, what is claimed and desired securedby Letters Patent is:

1. A pipe boring jack comprising: a supporting frame; a carriageslidably mounted in said frame; a tubular member adapted to receive thepipe mounted on said carriage; clutching means on said tubular memberfor clutching said pipe; lever means hingedly mounted on said frame andextending upward alongside said carriage; means projecting from saidcarriage into engagement with said lever means for moving the carriageforwardly; "an arcuate toothed rack formed on said lever means; and aring gear on said tubular member meshing with the teeth of said rack torotate the former with each forward movement of said lever means theteeth of said rack being suillciently long to allow the teeth of thering gear to slide therealong so as to remain in mesh during therelative movement between said carriage and said Supporting frame.

2. A pipe forcing jack comprising: a base frame; end members arisingfrom said frame; parallel bars extending between said end mem-Y bers; acarriage slidably mounted on said bars a tubular member rotatablymounted on said carriage for receiving a pipe; clutching means in saidtubular member for engaging said pipe; a lever pivotally mounted on saidbase frame; a pin projecting from said carriage into an elongated slotin said lever to move the carriage forwardly with each forward movementof said lever; an arcuate toothed rack projecting from said lever; andan annular toothed gear mounted on said tubular member and meshing withsaid rack so that each forward movement of said lever willsimultaneously rotate said gear and move said carriage forwardlyrelative to the pivot point of said lever, the teeth of Said arcuaterack aligning with the axis of said tubular member at their point ofcontact with the teeth of said gear and being sufficiently long toremain in mesh with said gear teeth at all relative positions betweensaid carriage and the pivot point of said lever.

3. A pipe forcing jack comprising: a base frame; end members arisingfrom said frame; parallel bars extending between said end members; acarriage slidably mounted on said bars; a tubular member rotatablymounted on said carriage for receiving a pipe; a ring gear rotatablymounted on said tubular member; pipe-engaging dogs hingedly mounted onsaid ring gear and extending tangentially inward through guide openingsin said tubular member so that rotation of said gear on said member willforce said dogs against said pipe; a lever hingedly mounted on saidframe and extending upward adjacent said carriage; a pin etxending fromsaid carriage into engagement with said lever for communicating themovements of said lever to said carriagey to move the latterlongitudinally along side parallel bars; and an arcuate toothed rackcarried by said lever in mesh with said'ring gear for rotating thelatter as it moves along said bars.

BRADA GUYER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

